Lamp adapter for two-filament lamps



1955 R. L. MARTIN ETAL LAMP ADAPTER FOR TWO-FILAMENT LAMPS 5 Sheets-Sheet 1 Filed April 16, 1963 FIGI FIGS

FIGS

INVENTORS ROBERT LEWIS MARTIN BY GEORGE BERTHEL BENANDER M014. uflwi .4 TTORNE Y Nov. 9, 1965 R. MARTIN ETAL LAMP ADAPTER FOR TWO-FILAMENT LAMPS 3 Sheets-Sheet 2 Filed April 16, 1963 FIGS INVENTORS ROBERT LEWIS MARTIN GEORGE BERTHEL BENANDER A TTORNE Y United States Patent 3,217,116 LAMP ADAPTER FOR TWO-FILAMENT LAMPS Robert L. Martin and George B. Benander, Cranston, Rl, assignors to General Electric Company, a corporation of New York Filed Apr. 16, 1963, Ser. No. 273,334 7 Claims. (Cl. ZED-41.03)

This invention relates to lamp sockets and, in particular, to an adapter mountable in a conventional lamp socket to permit the use of double-filament lamps therewith.

Many incandescent electric lamps today are manufactured with two filaments in order to provide multiple levels of light. Some of these multiple-filament lamps are manufactured with their filaments in series relation while others have their filaments in parallel arrangement. In either case the multiple-filament lamps require special lamp sockets having special switching arrangements for controlling the filaments because conventional lamp sockets are adapted for use with only the more common single-filament electric lamp.

Multiple-filament lamps having plug portions adaptable for mounting in conventional lamp sockets and incorporating switching structures within the lamp itself have been unsuccessful because the use of a separate switch arrangement in each lamp results in excessively expensive multiple-filament lamps.

Prior attempts to provide a separate adapter for use with conventional lamp sockets and multiple-filament lamps have had a number of disadvantages. For example, they have been too long to be used aesthetically with lamp fixtures, they have been awkward to install in and remove from lamp sockets, and they have been difiicult to operate.

One object of this invention is to provide an improved adapter which may be easily inserted in or removed from a conventional single-filament lamp socket and which provides a convenient and easily operated switch mechanism for a multiple-filament lamp.

Another object of this invention is to provide such an adapter having its contact switching mechanism arranged so as to provide a short and compact adapter structure.

A further object of the invention is to provide an improved adapter which functions equally well with multiplefilament lamps having their filaments connected in series and multiple-filament lamps having their filaments connected in parallel.

Another object of this invention is to provide an adapter having contacts so constructed and arranged as to insure that multiple-filament lamps used therewith may be securely and operatively mounted in the socket portion of the adapter.

Further objects and advantages of this invention will become apparent as the following description proceeds, and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of this invention, reference may be had to the accompanying drawings in which:

FIG. 1 is a longitudinal sectional view of an adapter incorporating one embodiment of the invention;

FIG. 2 is a longitudinal sectional view taken along the line 2-2 as shown in FIG. 1;

FIG. 3 is a sectional view taken along the line 3-3 as shown in FIG. 1 and showing the contacts in a first position;

FIG. 4 is a view similar to FIG. 3 with the contacts in a second position;

FIG. 5 is a view similar to FIG. 3 with the contacts in a third position;

Patented Nov. 9, 1965 ice FIG. 6 is a perspective view of the ring conductor utilized in the invention showing one embodiment of its interrupted portion;

FIG. 7 is a perspective view of the spring-loaded plunger utilized with the intermediate contacts of the invention;

FIG. 8 is a longitudinal sectional view similar to FIG. 1 embodying a modified form of the invention;

FIG. 9 is a transverse sectional view of the embodiment illustrated in FIG. 8 showing the contacts in a first position;

FIG. 10 is a transverse sectional view similar to FIG. 9 showing the contacts in a second position;

FIG. 11 is a longitudinal sectional view similar to FIG. 2 showing another modified form of the invention;

FIG. 12 is a transverse sectional view of the embodiment illustrated in FIG. 11 showing the contacts in a first position;

FIG. 13 is a transverse sectional view similar to FIG. 12 showing the contacts in a second position;

FIG. 14 is a transverse sectional view similar to FIG. 12 showing the contacts in a third position; and

FIG. 15 is a transverse sectional view similar to FIG. 12 showing the contacts in a fourth position.

Referring now to FIGS. 1 and 2, an adapter 1 is formed by a pair of semi-cylindrical members 2 which are brought together along mating surfaces 3 to provide a generally cylindrical adapter structure. The adapter 1 has a plug section 4 adapted to be screwed into a conventional lamp socket and a socket section 5 adapted to receive a multifilament lamp. A screw shell 6 is spun and staked on the outer surface of the plug section 4 to serve as a ground contact with the conventional lamp socket and to hold the two semi-cylindrical members 2 together at their lower ends. An annular flange 7 extends outwardly between the plug section 4 and the socket section 5 so as to provide a surface which may be easily grasped in order to insert the adapter in or remove it from a conventional lamp socket. Additionally, the annular flange 7 provides a shelf which supports a rotatable annular switch operating member 8.

The switch operating member 8 fits around the outer surface of the semi-cylindrical members 2 and is held in place by means of a ring clip 9 mounted in a groove 10. Clip 9 also secure-s together the two semi-cylindrical members 2 adjacent the outer end of the socket section 5. A ring conductor 11 is provided along the inner surface of the switch operating member 8 at its lower end. As may be better seen in FIG. 6, the ring conductor 11 is provided with a continuous portion 12 and an interrupted portion 13. Although a particular configuration is shown in FIG. 6 it will become apparent that this configuration may be changed in order to provide for various modes of operation.

A ground contact 14 is mounted in the socket section 5 and extends downwardly into the plug section 4 where it is bent outwardly so that its lower end is brought into firm contact with screw shell 6. Screw threads 15, provided in socket section 5, are interrupted to provide an opening for ground contact 14. When a multiple-filament lamp is mounted in the socket section its screw shell ground contact engages ground contact 14 and the lamp ground contact is electrically connected to the ground contact of the conventional lamp socket through the ground contact 14 and the screw shell 6.

In the particular embodiment shown in FIGS. 1-6, a double-filament lamp is employed and, for the sake of clarity, the lamp is represented schematically by filaments 16 and 17 which are connected to ground contact 14, intermediate contact 18 and center switch contact 19. Filaments 16 and 17 have different resistance values to produce diiferent levels of light. It will be assumed filament 17 has the lower resistance value although it will be obvious that the invention will function equally well regardless which has the higher value. A line contact 20, provided with a hook portion 21 that extends through the outer end of the plug section 4, extends longitudinally through the plug section 4 and outwardly along the annular flange 7 to contact the continuous portion 12 of ring conductor 11. The intermediate contact 18 and center switch contact 19 are generally horizontally disposed, extending inwardly over the annular flange 7 so as to selectively connect the filaments 16 and 17 to the interrupted portion 13 of the ring conductor 11. The contacts 18, 19 and are provided with resilient arms 18a, 19a and 20a, respectively, to insure good electrical contact with the ring conductor 11. In the embodiment of the adapter shown in FIGS. 16 the interrupted portion 13 of the ring conductor 11 is formed as shown in FIG. 6, that is to say, with two sections of conductors, such as 13a and 13b, then one blank section, such as 13c, successively around the circumference of the ring conductor 11 for a total of 12 sections.

The manner of operation of the first embodiment of the adapter to secure three levels of light is shown in FIGS. 3-5. With the switch operating member 8 in the position shown in FIG. 3, wherein the lowest level of illumination is secured, the line contact 20 is in engagement with the continuous portion 12 and the intermediate contact is in engagement with conductor section 13d of the interrupted portion 13 and center switch contact 19 is in register with blank section 13c. With this switch setting, electric current provided through the conventional lamp socket, flows through time contact 20, ring conductor 11, intermediate contact 18, filament 16, ground contact 14 and screw shell 6. Filament 17 is connected to switch contact 19, which is in register with blank section 130 of ring conductor 11. Therefore, filament 17 is not provided with electric power.

To secure the next level of illumination the switch operating member 8 is rotated to the position shown in FIG. 4, at which time center switch contact 19 is in engagement with conductor section 13c while intermediate contact 18 engages blank section 13 With this setting, the electric current flows through line contact 20, ring conductor 11, cent-er switch contact 19, filament 17, ground contact 15 and screw shell 6. Filament 16 is connected to intermediate contact 18, which is in register with blank section 13f of ring conductor 11. Therefore, filament 16 is not provided with electric power.

To secure the highest level of illumination the switch operating member 8 is rotated to the position shown in FIG. 5, at which time intermediate contact 18 is in engagement with conductor section 13g and center switch contact 19. is in engagement with conductor section 13h. With this setting electric current flows through line contact 20, ring conductor 11, then in parallel through a first path having intermediate contact 18 and filament 16 and a second path having switch contact 19 and filament 17, then through ground contact14 and screw shell 6. Power is thus provided tofilaments 16 and 17 in parallel.

It will be noted that this embodiment of the adapter does not provide for an oit position for the multi-filament lamp. On and ofi? settings of the multi-filament lamp may be accomplished simply by utilizing the on-ofi switch of the conventional lamp socket. It is, of course, apparent that, if an off position of the adapter is desired, it can be provided by altering the configuration of interrupted portion 13.

The embodiment of this invention shown in FIGS. 8-10 is designed for use with a lamp having two filaments 22 and 23 in series, with an intermediate tap-off 24 in order to obtain two levels of illumination.

The switch operating member 25 is similar to switch operating member 8 except that it is formed to receive a ring conductor 26 having an interrupted portion 27 with four conductor sections, 27a, 27b, 27c and 27d, arranged alternately with four blank sections, 27e, 27f, 27g and 2711. Line contact 28 is formed and mounted so as to contact filament 23, while intermediate contact 29 is arranged so as to selectively connect conductor sections 27a, 27b, 27c and 27d of interrupted portion 27 to the intermediate tap-ofl. 24, and switch contact 30 is disposed so as to selectively connect line contact 28 to conductor sections 27a, 27b, 27c and 27d of interrupted portion 27. Intermediate contact 29 and switch contact 30 are provided with resilient arms 29a and 30a, respectively, to insure good electrical contact with ring conductor 26. The other end of filament 22 is connected to ground contact 14.

To secure the higher level of illumination the switch operating member 25 is rotated to the position shown in FIG. 9, at which time intermediate contact 29 and switch contact 30 contact conductor sections 27a and 270, respectively. Electric current flows through line contact 28, ring conductor 26, intermediate contact 29, intermediate tap-oif 24, filament 22, ground contact 14, and screw shell 6. Since the resistance of filament 23 is higher than the sum of the resistances of switch contact 30, ring conductor 26, intermediate contact 29 and center tap-oh. 24, filament 23 is essentially shorted out.

To secure the lower level of illumination, switch operating member 25 is rotated to the position shown in FIG. 10, at which time intermediate contact 29 and switch contact 30 are in register with blank sections 27e and 27g, respectively. Since intermediate contact 29, switch contact 30 and ring conductor 26 are not in the electric circuit, electric current will flow through line contact 28, filaments 23 and 22 in series, ground contact 14 and screw shell 6.

This cycle is repeated as the switch operating member is rotated in a step-by-step clockwise manner. As in the first embodiment, on and 01f settings are not provided by the adapter and may be accomplished by utilizing the onoff switch of the conventional lamp socket.

The embodiment shown in FIGS. 11-15 can be used either with parallel-filament lamps discussed with the embodiment of FIGS. l-6 or with series-filament lamps discussed with the embodiment of FIGS. 8-10. A difierent sequence of illumination levels will be obtained depending on the type of multiple-filament lamp used. In this embodiment, switch operating member 31 is similar to switch operating member 8 of the first embodiment except that is it formed to receive ring conductor 32 having a different interrupted portion 33. The interrupted portion 33 has eight sections arranged in the order of three conductor sections followed by a blank section. Ground contact 14, intermediate contact 18, center witch contact 19 and screw shell 6 are the same as in the embodiment disclosed in FIGS. 1-6; however, line contact 34 is shaped so that a resilient arm 34a provided at its inner end will selectively engage conductor sections of the interrupted portion 33 rather than the continuous section.

Assuming a parallel-filament lamp as in FIGS. 1-6 is installed in the socket portion, with the switch operating member 31 in the position shown in FIG. 12, line contact 34 is in register with a blank section 33a. Since power is provided to the lamp through ring conductor 32 and is not in contact with line contact 34, the lamp is off.

To obtain a first or low level of illumination switch operating member 31 is rotated to the position shown in FIG. 13. In this position line contact 34 is in contact with conductor section 33b and intermediate contact 18 is in contact with conductor section 330 while center switch contact 19 is in register with blank section 33d. With this switch setting electric current flows through line contact 34, ring conductor 32, intermediate contact 18, filament 16, ground contact 14 and screw shell 6. Since filament 17 is connected to center switch contact 19, which is in register with blank section 33d, no current flows through filament l7.

contact.

T o obtain the next higher level of illumination, switch operating member 31 is rotated to the position shown in FIG. 14. In this position line contact 34 is in contact with conductor section 33c, and center switch contact 19 is in contact with conductor section 33 while intermediate contact 18 is in register with blank section 330. With this switch setting electric current flows through line contact 34, ring conductor 32, center switch contact 19, filament 17, ground contact 14 and screw shell 6. Since filament 16 is connected to intermediate contact 18, which is in register with blank section 33a, no current flows through filament 16.

To obtain the highest level of illumination, switch operating member 31 is rotated to the position shown in FIG. 15. In this position line contact 34 is in contact with conductor section 33g, intermediate contact 18 is in contact with conductor section 33b and center switch contact 19 is in contact with conductor section 33h. With this switch setting electric current flows through line contact 34, ring conductor 32, then in parallel through a first path having intermediate contact 18 and filament 16 and a second path having center switch contact 19 and filament 17, then through ground contact 14 and screw shell 6. Power is thus provided to filaments 16 and 17 in parallel.

Thus, when a parallel-filament lamp is used, illumination levels of 0E, low, medium and high are obtained.

'When a series-filament lamp such as the one'shown in FIG. 8 is used with this embodiment, the switch setting shown in FIGS. 12-15 will give illumination levels of off, high, low and high.

Double-filament lamps are usually constructed with a central contact disposed within and spaced from a ring One filament lead is attached to the ring contact by soldering it to the outside of the ring contact, thus producing a bump of solder on the surface of the ring contact. When lamps thus produced are mounted in an adapter of the type just described, the intermediate contact 18 tends to dig into the bump of solder and may interfere with proper seating of the lamp. .A construction of the intermediate contact for overcoming this difiiculty is shown in FIG. 7. There an intermediate contact 35, corresponding to intermediate contact 18 in the embodiment of FIGS. 1-6 and FIGS. 11- 15 and intermediate contact 29 in the embodiment of FIGS. 8-10, is provided with a longitudinally extending plunger 36. The plunger 36 is mounted on an inwardly extending foot 37 and is biased away from the foot 37 by spring 38. The inwardly extending foot 37 is engaged in a small recess 39 to prevent movement of the foot 37. This'arrangement provides a resilient intermediate contact and thereby enables the user to more easily install the lamp properly in the adapter.

While we have shown particular embodiments of our invention, we do not desire our invention to be limited to the particular constructions shown and we intend the appended claims to cover all modifications within the spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An adapter mountable in a conventional lamp socket to permit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical inter-connections,

(c) rotatable switching means, including an annular switch-operating member, mounted around the outer surface of said socket portion for selectively varying said electrical interconnections to provide for multiple levels of illumination, and

(d) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating insertion of said adapter into and removal of said adapter from the conventional lamp socket and supporting said rotatable switching means.

2. An adapter mountable in a conventional lamp socket for use with double-filament lamps having a central contact surrounded by a ring contact spaced from the central contact on the base of the lamp, comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical interconnections,

(c) rotatable switching means, including an annular switch-operating member, mounted around the outer surface of said socket portion for selectively varying said electrical interconnection to provide for multiple levels of illumination, and

(d) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating insertion of said adapter into and removal of said adapter from the conventional lamp socket and supporting said rotatable switching means,

(e) said contact means including an intermediate contact having a vertically movable, spring biased plunger disposed in the inner end of said socket portion and adapted to provide a resilient contact with the ring contact, whereby proper seating of the double-filament lamp in said socket portion is facilitated.

3. An adapter mountable in a conventional lamp socket to permit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical interconnections,

(c) rotatable switching means mounted around the outer surface of said socket portion for selectively varying said electrical interconnections to provide for multiple levels of illuminating,

(d) said switching means having an outer housing,

(6) said switching means also having a generally ringshaped conductor including a continuous section and an interrupted section for selectively contacting portions of said contact means,

(1) said ring-shaped conductor being disposed within said outer housing and radially outside said body member for rotation with said outer housing, whereby alterations in said electrical interconnections are made radially outside said body member,

(f) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating insertion of said adapter into and removal of said adapt-er from the conventional lamp socket and supporting said rotatable switching means.

4. An adapter mountable in a conventional lamp socket to permit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp, 7

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical interconnections,

(c) rotatable switching means mounted around the outer surface of said socket portion,

((1) said switching means having an outer housing,

(c) said switching means also having a generally ringshaped conductor including a continuous section and an interrupted section comprising a plurality of spaced conductor sections,

(1) said ring-shaped conductor being disposed on the inner surface of said outer housing and radially outside said body member,

(2) said spaced conductor sections selectively contacting portions of said contact means radially outside said body member to vary said electrical interconnections to provide for multiple levels of illumination,

(f) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating insertion of said adapter into and removal of said adapted from the conventional lamp socket and supporting said rotatable switching means.

5. An adapter mountable in a conventional'lamp socket to permit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion and providing a plurality of electrical interconnections,

(c) rotatable switching means mounted around the outer surface of said socket portion for selectively varying said electrical interconnections to provide for multiple levels of illumination,

(d) said switching means including a ring conductor having a continuous section and an interrupted section,

(c) said contact means including:

(1) a longitudinally extending line contact provided at one end with a section forming a contact surface at the, outer end of said plug portion and provided at its other end with a resilient arm to engage said continuous section of said ring conductor,

(2) an intermediate contact provided with a resilient arm to selectively engage said interrupted section of said ring conductor, and

(3) a switch contact spaced from said intermediate contact and provided with a resilient arm to selectively engage said interrupted section of said ring conductor, whereby the electrical interconnections of said contact means may be varied by rotating said switching means,

(f) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating insertion of said adapter into and removal of said adapter from the conventional lamp socket and supporting said rotatable switching means.

6. An adapter mountable in a conventional lamp socket topermit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical interconnections,

(c) rotatable switching means, including an annular switch operating member, mounted around the outer surface of said socket portion for selectively varying said electrical interconnections to provide for multiple levels of illumination,

(d) said switching means including a ring conductor having a continuous section and an interrupted section,

(e) said contact means including:

(1) a longitudinally extending line contact provided at one end with a section forming a contact surface at the outer end of said plug portion and provided at its other end with a transversely disposed resilient arm,

(2) an intermediate contact including a resilient arm to selectively engage said interrupted section of said ring conductor, and

(3) a switch contact bearing against said line contact and provided with a resilient arm to selectively engage said interrupted portion of said ring conductor, whereby the electrical interconnections of said contact means may be varied by rotating said switching means,

(f) an annular flange extending outwardly between said plug portion and said socket portion to provide a finger grip for facilitating the insertion of said adapter into and removal of said adapter from the conventional lamp socket and supporting said rotatable switching means.

7. Au adapter mountable in a conventional lamp socket to permit use of double-filament lamps therewith comprising:

(a) a body member including a plug portion adapted to "be inserted in a conventional lamp socket and a socket portion adapted to receive a double-filament lamp,

(b) contact means in said body member extending between said plug portion and said socket portion, and providing a plurality of electrical interconnections,

(c) an annular flange extending outwardly between said plug portion and said socket portion toprovide a finger grip for facilitating insertion of said adapter into and removal of said adapter from the conventional lamp socket, and

(d) rotatable switching means mounted around the outer surface of said socket portion for selectively varying said electrical interconnections to provide for multiple levels of illumination,

(e) said switching means including a ring conductor having a continuous section and an interrupted section,

(f) said contact means including,

( 1) a longitudinally extending line contact provided at one end with a section forming a contact surface at the outer end of said plug portion and provided at its other end with a resilient arm to selectively engage said interrupted section of said ring conductor,

(2) an intermediate contact including a resilient arm to engage said interrupted section of said ring conductor, and

(3) a switch contact positioned opposite said intermediate contact and provided with a resilient arm to engage said interrupted section of said ring conductor, whereby the electrical interconnection of said contact means may be varied by rotating said switching means.

References Cited by the Examiner UNITED STATES PATENTS 768,847 6/04 Elliott 20051.03 807,671 12/05 Gremrnels ZOO-51.02 1,465,735 8/23 Lavine 2005l.04 2,222,655 9/40 Dulberg 20051.03 2,786,909 3/57 Goldman ZOO-51.04

BERNARD A. GILHEANY, Primary Examiner, 

1. AN ADAPTER MOUNTABLE IN A CONVENTIONAL LAMP SOCKET TO PERMIT USE OF DOUBLE-FILAMENT LAMPS THEREWITH COMPRISING: (A) A BODY MEMBER INCLUDING A PLUG PORTION ADAPTED TO BE INSERTED IN A CONVENTIONAL LAMP SOCKET AND A SOCKET PORTION ADAPTED TO RECEIVE A DOUBLE-FILAMENT LAMP, (B) CONTACT MEANS IN SAID BODY MEMBER EXTENDING BETWEEN SAID PLUG PORTION AND SAID SOCKET PORTION, AND PROVIDING A PLURALITY OF ELECTRICAL INTERCONNECTIONS, (C) ROTATABLE SWITCHING MEANS, INCLUDING AN ANNULAR 